In a 1500 point list setup like this. I personally would:
I would change the
CSM squads a little.
(x2 Squads of 2 melta, Power Weapon . x2 Squads of Flamer, Power Fist)
It's a little crazy gearing every single squad to handle a Walker, specially at 40 points total for the upgrade. But two squads like that would help a lot,
PFs instant kill most
HQ characters and stuff too, so the flamers will help when charging their squad.
You only have roughly 1300 points on the list you posted as well.
I could see this list adding a Greater Daemon and having a lot of fun with it's
MC spam. But since both
HQs are lash princes (or at least one will be) I would recommend something along the lines of Havoks, Oblits, Dreads (maybe?) or 2 vindicators or 2 defilers. Just some nice heavy support to take heat off all the rhinos, and to get a couple good shots off on lashed units.
Your current list doesn't have any Chosen, but their also a good option for Anti-horde, or anti-tank. Just gear them specifically for one role, make them cheap as heck and have a fun suicide mission
You're getting some good input from a couple of people here, hope mine helps as well. Good luck!